A Computer Memory Primer

Here is a quick list of the different types of memory found within a typical computer workstation / server.

SRAM (Static RAM) DRAM (Dynamic RAM) DRAM DRAM DRAM DRAM DRAM DRAM DRAM
SIMM SIMM DIMM DIMM DIMM DIMM DIMM RIMM
SDR
SDRAM
DDR(1) SDRAM DDR2 SDRAM DDR3 SDRAM DDR4
SDRAM
2000 2003 2007 2012
32 Bit 32 Bit 64 Bit 64 Bit 64 Bit 64 Bit 64 Bit
1 –> 128 MB
30 Pin 72 Pin 168 Pin 184 Pin 240 Pin 240 Pin (different notch to DDR2) 284 Pin
SO-DIMM = 200 Pin SO-DIMM = 200 Pin (different notch to DDR1) SO-DIMM = 204 Pin
DDR3L is a Low Voltage Version
  • SRAM (Static RAM) is mainly used within the CPU Cache. It is faster, but more expensive to produce than DRAM.
  • DRAM (Dynamic RAM) is essentially Computer Main Memory
  • SIMM = Single Inline Memory Module
  • DIMM = Dual Inline Memory Module. These can be ECC and / or Registered (Buffered) in Servers and High End Workstations. So, “standard” DIMM modules are also known as UDIMM (Unregistered), whilst registered memory is RDIMM
  • ECC = Error Correction Code. An extra “parity” chip on the memory board is used to detect and correct errors. Due to the additional chip (and processing required), ECC RAM is both more expensive and slower than Non-ECC Memory.
  • Registered / Buffered Memory.
  • SDRAM = Synchronous Dynamic Random Access Memory
  • SDR = Single Data Rate
  • DDR = Double Data Rate
  • SO-DIMM = Small Outline Dual Inline Memory Module (Laptop Memory)
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Remote Administration of VPN Client Computers

Within the Microsoft Environment, Remote VPN Client Computers do not register themselves within DNS. Additionally, DHCP entries are attributed to “RAS” rather than the host name of the clients.

This means that remotely administering a VPN Client machine using the Host Name isn’t going to be possible. However, I did have some success using the IP Address of the Client.

So, how do we find the IP Address of the Remote Client?

You can find a list of currently connected “Remote Access Clients” within the “Routing and Remote Access” snap-in

VPN 001

Administrative Tools => Routing and Remote Access => Select Server => Remote Access Clients => Status. Make a note of the IP Address for the Client.

You can then use IP Address (rather than the Host Name) to connect to the Client with the usual Administration Tools.

VPN 003

Uninstalling Sage Construct

If you run into problems trying to Re-Install or Upgrade Sage Contruct, it is often neccesary to completely remove the existing Installation. The following text describes how to completely remove Sage Construct from a Workstation:

[1] Uninstall all “R5” Programs using Control Panel
[2] Uninstall the “Construct” Program Using Control Panel
[3] Use the “Windows Installer Cleanup” Utility to remove any remaining “R5”; “Dynamic Catalog Editor” and “Construct” installations: http://support.microsoft.com/kb/290301 
[4] Remove the “C:\Program Files\Sage\Construct” Folder (if it is still present)
[5] Remove any remaining “R5” Folders from within “C:\Program Files\Sage\”
[6] Remove the “C:\Program Files\Sage\DMO” Folder (if it is still present)
[7] Using the Registry Editor, (search for and) remove any Registry Keys that SPECIFICALLY refer to “R5 Share” #
[8] Using the Registry Editor, (search for and) remove and Registry Keys that SPECIFICALLY refer to “R5 System Manager” # 
[9] Using the Registry Editor, (search for and) remove and Registry Keys that SPECIFICALLY refer to “ATW” # 
[10] Cleardown the “C:\Windows\Temp” Folder
[11] Cleardown “C:\Documents and Settings\*CurrentUser*\Local Settings\Temp” for the Current User

# When searching the registry, pay particular attention to any keys within:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Current Version\Uninstaller
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Current Version\Installer
HKEY_CURRENT_USER\Software\Microsoft\Windows\Current Version\Uninstaller
HKEY_CURRENT_USER\Software\Microsoft\Windows\Current Version\Installer

Running the Sage Construct Installation routine:
Do not use an Account with a Roaming User Profile when installing Sage Construct. More often than not, the installation routine will fail because it believes the package has already been installed.

Key Words:
“Unable to find the upgrade information for R5 System Manager”
“R5 System Manager Upgrade Required”

Disclaimer:
These instructions involve editing the Computer Registry and are provided without Warranty or Liability. E&OE.

Disabling the “http://companyweb” Annonyance

If you are running Small Business Server 2008, your users may be tired of the system constantly resetting their Internet Explorer  “Home Page” back to http://companyweb. This feature can be disabled by starting up the “Group Policy Management” Console (gpmc.msc) and then editing the “Windows SBS User Policy” GPO . The setting you need to change can be found within: Windows SBS User Policy => User Configuration => Windows Settings => Internet Explorer Maintenance => URLs / Important URL’s => Home Page URL. Uncheck “Customise Home Page URL” (or replace “companyweb” with an more suitable option).

WARNING: “Shared Folders” and Microsoft Virtual PC

Microsoft Virtual PC includes a “Shared Folder” facility to enable the Guest Operating System to access files on the Host’s Hard Disk Drive. This seems to work fine for small files, but I recently discovered this to be extremely unreliable when transferring very large files. In my case, this was “forklifting” 5GB worth of Exchange Server Database files. The files appeared to copy across correctly, but in fact they were badly corrupted in transit – and failed to mount properly on the Guest OS. I re-tried this several times (even to the point of creating some “.par” parity files to accompany them). As a result of this experience, I would recommend utilising “Network Shares” to transfer ALL files between the Guest & Host Operating systems. I have so far found this mechanism to be flawless…